A novel fibrous sorbent, amidoxime-grafted activated carbon fibers (ACFs-AO), was prepared using a chemical grafting method and tested for the efficient removal of uranium from aqueous solution. The sorbent was characterized using X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), elemental analysis, thermogravimetric analysis (TGA) and Brunauer-Emmett-Teller (BET). The effects of pH, contact time, initial concentration, and temperature on the sorption of U(VI) were investigated. The sorption of U(VI) on ACFs-AO obeyed pseudo-second-order model and Langmuir isotherm. The sorption capacity of ACFs-AO for U(VI) (about 191.6 mg/g) was much higher than that of activated carbon fibers (ACFs) (about 70.52 mg/g), which was mainly attributed to surface complexation between U(VI) and the amidoxime group on ACFs-AO. Additionally, the thermodynamic parameter results showed that the sorption process of U(VI) was spontaneous, feasible, and endothermic. Moreover, ACFs-AO adsorbed U(VI) selectively in an aqueous solution containing competitive ions, and was regenerated and reused efficiently. The findings of this work indicate that ACFs-AO could be a promising sorbent for the effective removal of U(VI) from aqueous solution.

中文翻译：

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合成a胺肟接枝的活性炭纤维可有效去除水溶液中的铀（VI）

使用化学接枝方法制备了一种新型的纤维状吸附剂，mid胺肟接枝的活性炭纤维（ACFs-AO），并进行了从水溶液中有效去除铀的测试。使用X射线光电子能谱（XPS），场发射扫描电子显微镜（FE-SEM），元素分析，热重分析（TGA）和Brunauer-Emmett-Teller（BET）对吸附剂进行表征。研究了pH，接触时间，初始浓度和温度对U（VI）吸附的影响。U（VI）在ACFs-AO上的吸附遵循伪二级模型和Langmuir等温线。ACFs-AO对U（VI）的吸附能力（约191.6 mg / g）远远高于活性炭纤维（ACFs）（约70.52 mg / g），这主要归因于U（VI）之间的表面络合）和ACFs-AO上的mid胺肟基。此外，热力学参数结果表明，U（VI）的吸附过程是自发的，可行的并且是吸热的。此外，ACFs-AO在含有竞争离子的水溶液中选择性吸附U（VI），并被有效地再生和再利用。这项工作的发现表明，ACFs-AO可能是从水溶液中有效去除U（VI）的有前途的吸附剂。